SanDisk has launched legal action against Infineon after the German chipmaker alleged its Flash memory technology infringes an Infineon patent.

The complaint, filed with the US District Court for Northern California, asks the court to rule that SanDisk hasn't infringed the patent, number 5,726,601, and that the patent is also invalid.

The patent, titled 'Integrated circuit and method for producing the same', was granted to Siemens in 1998, just under two years after it was filed. Since Infineon is Siemens' spun-off semiconductor operation, it presumably now administers the intellectual property.

The patent describes "an integrated circuit having contacting locations that are connectable to external terminals of the integrated circuit through bonding wires". It also "relates to a method for producing the integrated circuit". As far as we can see, the patent doesn't explicitly refer to Flash, but it does refer to NAND gate logic, a key component of Flash memory.

SanDisk certainly believes it relates to Flash since it accuses Infineon of attempting to cause it harm now that the two companies are competitors, a result of Infineon's decision to move into the Flash market. ®